St. Mark’s Cathedral is the seat of Egypt’s Orthodox Christian church and is home to the office of its spiritual leader, Pope Tawadros II.

The explosion came two days after twin bombings in the city killed six policemen and a civilian. The Hassam Movement, a terrorist group which has claimed a string of recent attacks, said it was behind those attacks, in a statement circulated on social media.

Terrorists have repeatedly attacked police and soldiers since the army overthrew Islamist president Mohamed Morsi in 2013 and unleashed a bloody crackdown on his followers.

Most of the attacks are carried out in the Sinai Peninsula in eastern Egypt by a branch of the ISIS jihadist group, which has killed hundreds of soldiers and policemen.

But terrorists have also targeted security forces and government officials in the capital.

Most of the Cairo attacks in recent months have been claimed by two little-known terrorist groups, Lawaa al-Thawra and the Hassam Movement.

Police say Hassam and Lawaa Al-Thawra are affiliated with Morsi’s Muslim Brotherhood movement, which was banned months after his overthrow and listed as a terrorist organisation.

The Brotherhood, which espoused grassroots work and change through elections, denies it is involved in violence.